President Trump attacked Sen. Kirsten Gillibrand (D-N.Y.) in a sexually suggestive tweet Tuesday morning that implied Gillibrand would do just about anything for money, prompting a swift and immediate backlash.

“Lightweight Senator Kirsten Gillibrand, a total flunky for Charles E. Schumer and someone who would come to my office 'begging' for campaign contributions not so long ago (and would do anything for them), is now in the ring fighting against Trump,” the president wrote. “Very disloyal to Bill & Crooked-USED!”

Lightweight Senator Kirsten Gillibrand, a total flunky for Chuck Schumer and someone who would come to my office “begging” for campaign contributions not so long ago (and would do anything for them), is now in the ring fighting against Trump. Very disloyal to Bill & Crooked-USED!

The tweet came as Trump is already facing negative publicity from renewed allegations from three women who had previously accused him of sexual harassment, which are coming amid the #MeToo movement that is roiling the nation and forcing powerful men accused of sexual misbehavior from their posts.

White House spokeswoman Sarah Huckabee Sanders disputed the characterization of Trump's tweet as sexually suggestive, telling reporters that “there’s no way this is sexist at all” and later adding: “I think only if your mind is in the gutter would you have read it that way.”

“He’s used that same terminology many times in reference to men,” Sanders added, arguing that Trump was motivated by his long-standing concern about the corrupting influence of money in politics.

The president ignored a reporter's question about the tweet after he signed a defense authorization bill shortly after noon.

The backlash and criticism was near instantaneous, with Gillibrand replying directly to Trump on Twitter. “You cannot silence me or the millions of women who have gotten off the sidelines to speak out about the unfitness and shame you have brought to the Oval Office,” she wrote.

At a news conference later on an unrelated issue, Gillibrand called Trump’s tweet “a sexist smear attempting to silence my voice.”

“I will not be silent on this issue, neither will women who stood up to the president yesterday and neither will the millions of women who have been marching since the Women’s March to stand up against policies they do not agree with,” she added.

Gillibrand once again called on GOP congressional leaders to launch investigations into the allegations made by women against Trump, saying, “It’s the right thing to do, and these allegations should be investigated. They should be investigated thoroughly. That is the right thing to do, and I’m urging them to do that — as should their constituents.”

Asked about her interactions with the president, Gillibrand told reporters that Trump was “just a supporter — a supporter of my first campaign.”

Several Democratic senators also rallied around Gillibrand, including Sen. Elizabeth Warren (D-Mass.), who pointedly asked Trump on Twitter whether he was trying to “bully, intimidate and slut-shame” Gillibrand.

Sen. Jeanne Shaheen (D-N.H.) also weighed in on Twitter, writing that there is “nobody tougher than @SenGillibrand & she won’t be intimidated. Women will continue to speak up.”

Gillibrand was attending a bipartisan Bible study Tuesday morning when Trump's tweet landed, and her phone was immediately filled with supportive and befuddled messages, wondering just what the president was thinking, a Gillibrand aide said.

Sen. James Lankford (R-Okla.), who was in the Bible study group with Gillibrand, later issued a statement, saying: “Respectful dialogue and disagreement sets a better example for our children and the world. Our leaders should focus on the issues, not personal attacks.”

Gretchen Carlson, the former Fox News personality whose lawsuit against Roger Ailes for sexual harassment led to the resignation of the late network chairman, also weighed in with a duo of tweets defending Gillibrand.

“What do u mean @SenGillibrand would 'do anything' for campaign contributions? By the way she isn’t a lightweight,” she wrote. In a second tweet, Carlson continued: “Sexual harassment is apolitical. Women will not be silenced no matter what party they are in. Period.”

Katty Kay, an anchor for BBC World News America, also took to social media to respond to the president's missive against Gillibrand, casting it in tweets as “clearly sexual” and “demeaning to women.”

“What is so maddening about the Gillibrand tweet is that women can be smart, work hard, become Senator and STILL get sexual c**p thrown at us,” she wrote. “Enough.”

Gillibrand met with Trump once in 2010, the Gillibrand aide said, and Trump's eldest daughter, Ivanka, who has tried to cast herself as a champion of women, attended the meeting,

On Monday, Gillibrand, a leading voice in Congress for combating sexual assault in the military, became the fifth Democratic senator to call on Trump to step down because of the allegations of sexual misconduct against him — accusations the president has denied and the White House dismissed again on Monday.

“President Trump has committed assault, according to these women, and those are very credible allegations of misconduct and criminal activity, and he should be fully investigated and he should resign,” Gillibrand said on CNN. “These allegations are credible; they are numerous. I've heard these women's testimony, and many of them are heartbreaking.”

On Tuesday, a sixth senator — Democrat Mazie Hirono of Hawaii — called on Trump to resign, citing his morning tweet targeting Gillibrand.

“@realDonaldTrump is a misogynist, compulsive liar, and admitted sexual predator,” she said. “Attacks on Kirsten are the latest example that no one is safe from this bully. He must resign.”

Trump’s attack on Twitter also coincided with a previously scheduled event led by at least 59 female House Democrats, who formally called on the House Oversight and Government Reform Committee to launch an investigation into allegations of sexual misconduct by the president. The oversight panel has the broadest subpoena power and investigatory mandate of any congressional committee. The female lawmakers had requested the investigation in a letter to the committee on Monday.

What Trump tweeted Tuesday “is grotesque, it took my breath away and it represents the conduct of a person who is ill-equipped to be the president of the United States,” Rep. Jackie Speier (D-Calif.) said at the news conference.

Rep. Lois Frankel (D-Fla.) said Democrats are seeking “a fair process” to review the allegations and allow the president to respond.

By Tuesday afternoon, more than 100 House Democrats had joined in on the calls to formally investigate Trump after the letter was opened up to male colleagues.

Senate Majority Leader Mitch McConnell (R-Ky.) declined to say whether Congress should investigate allegations of sexual misconduct against Trump, saying, “We’re focused on the Senate,” and that his chamber’s ethics committee can only investigate allegations against senators.

“What we’re in charge of here is the Senate,” McConnell told reporters.

But he declined to join other Democrats calling for a formal investigation of allegations of sexual misconduct of Trump, saying he would let the comments of other Democrats speak for themselves.

Gillibrand, New York's junior senator and a rising political star, is widely considered a likely 2020 presidential candidate against Trump, and the president's Twitter assault Tuesday offered an early glimpse of just how vicious the next race for the White House could become.

Brian Fallon, a spokesman for Hillary Clinton's 2016 presidential campaign, called Trump's tweet “disgusting” but also noted, “It will make the Gillibrand folks ecstatic,” implying that the sparring with Trump would raise her profile.

Gillibrand, however, does have her critics. After she said in November that Bill Clinton should have resigned as president after his inappropriate affair with White House intern Monica Lewinsky, longtime Hillary Clinton adviser and confidant Philippe Reines excoriated her on Twitter for being ungrateful and two-faced.

“Senate voted to keep POTUS WJC. But not enough for you @SenGillibrand? Over 20 yrs you took the Clintons’ endorsements, money, and seat. Hypocrite. Interesting strategy for 2020 primaries. Best of luck,” Reines wrote.